Corrugated metal culvert.



openings 14 of the femaleend of one section and passed through the slots 13 of the'male end of the adjoining section when the sections arc screwed together a .certain predetermined distance, as shown clearly in Fig. 2. The distance is preferably predetermined by forcing a portion of the metal of the female end of the section inwardly and forming a stop 15, which limits the screwing movement of the parts and brings the openings 14 of one section in line with the slots 13 of the adjacent section, the purpose of these bolts being to securely hold the sections rigidly in position relative to each other, even though the screw threaded portions are not absolutely perfectly formed on the ends of the sections, and permits of the corrugated sections being inserted into the trench in which they are placed, with but little care, and allowing them to be roughly handled, and also prevent their being forced apart in case of settling of the dirt. This construction-also enables the ordinary bolts to be used at the ends of the sections in securing them together' temporarily, for by the time these bolts became rusted or broken, on account of rust, they will be no longer needed, as the culverts by that time will assume a permanent position in the earth.

ln practical use, cach section is constructed from rolled or stamped metal, and are` then rolled into tubular torm, and held in tubular form by the rivets or other securing means entering the openin s 10. `The sections are preferably shippe separately, but

a number may be'joined together to form the length of culvert desired, or any desirable number joined together that ma be easily handled. The sections are readi y attached to and detached from each other by the mechanism shown, so that they may be readily and easily set up in position for use, and owing to the simple arrangement of parts, the necessity of having mechanics put them together is obviated. Vhen the parts are thus'firmly secured together andthe complete culvert is fornied,it will be seen, that, owing to the spliral corrugations, the water passing throug the meta will easily cleanse the culvert andprevent sand and dirt accumulating in it to a great extent.

Having thus described. my invention, what I claim and desire to secure byLetters Patent of the United States, therefor is f 1. An improved culvert, formed of a sin le piece of sheet meta-l arran ed in tubu ar form-'and having one longitu inal edge overlapping the other longitudinal edge and conarra'nged spirally to strengthenthe culvert and to form screw-threaded ends, one end nected therewith bylmeans suchas rivets,

said culvert being provided throughout its' entire lengthwith .reinforcing corrugations being provided with transverse siots and the other` with holes to receive fastening means such as bolts to connect the two sections together.

- 2. An improved culvert, formed of a single piece of sheet metal arranged in tubular form with its longitudinal edges in overlapping positions and provided with openings to receive fastening devices, said culvert also provided with transverse slotsat one end and openings at the other end to receive fastening` means for connecting two culvert sections together, said culvert being also )rovided with spiral corrugations where y the end of one section may be screwed into the end of a mating section, said openings at the longitudinal edges of the section being arranged to receive fastening devices either before or after two sections have been connected to ether, so that the end of one section may be slightly expanded before being screwed on to the end of the mating section and the'fastening de vices placed 1n said holes after two sections are connected together.

3. An improved culvert, comprising a sheet metal body portion having spiral corrugations at its ends and also havin an in wardly projecting portion formed integral with the material of which the culvert is formed, said projection being arranged to limit the movement of a mating culvert section at the end Iadjacent to said projection.

.4. An improved culvert, comprising a, sheet metal body portion having spiral corrugations and also having at one end a series of transverse slots and at the other end a series of transverse holes, said parts bein" so arranged that one section may be screwc( into the end of a mating section and bolts or the like extended through the holes in one end and through the slots in the other end` said slots bein so arranged that the endof the culvert containing them may be slightly expanded to receive a mating culvert section without interfering with the insertion of bolts therein.

5. A culvert section formed of sheet metal, having spiral corrugations throughout its length for strengthening and rem- Jforcing it and for formin screw threads at the ends, so thatl one en of said culvert section may be screwed into a mating culvert section and said culvert sections held rigidly together by the spiral corrugations, and means near one end of the culvert section for limiting its screwing movement relative to a mating culvert section Des Moines, Iowa, Jan. 15, 1908.

JOSEPH RALPH ORWlG.

lVitnesses t S. F. CHRISTY, F. C. DAHLEnG. 

